Roll scouring block



June 28 1932. 53 BUELL 1,864,581

ROLL SCOURING BLOCK F iled Oct. 7, 1929 INVENTOR FRANK L. suau.

BY wag-ma: C. "Zn/(a7 ATTORNEY Patented June 28, 1932 UNITED STATES FRANK L. BUELL, or NIAGARA FALLS, NEW YORK, AssreNoR ro 'rnE cARBoRUNnum COMPANY, or NIAGARA FALLS, NEW YORK, A CORPORATION or PENNSYLVANIA ROLL SCOURING BLOCK 7 Application filed October 7, 1929]. Seria 1 No.;398,048. I

The present invention relates to roll scouring blocks for use in keeping rolls (such as drical surfaces are mentioned particularly here as the subject of operation, modifications of my design may be used in finishing internal cylindrical surfaces such as engine cylinders, pump cylinders, and the like. The usual type of scouring block is in the form of a brick or block made of artificially bonded abrasive material. In using a scouring block it is mounted on a plank about 8 feet long at a distance of about 1 foot from the end of the plank. The plank isslidably and rotatably mounted on a rod which is supported a short distance above the surface of a roll, the rod lying parallel to the axis of the roll to be scoured. The block is on the under side of the plank and is pressed against the roll by a workman who puts his weight on the end of the plank remote from the pivot. If the weight of the workman be 150 pounds the force on the abrasive surface of the block is about 1200 pounds in the example we have given. When the particular portion of the wheel on which the block has been hearing is sufiiciently scoured the plank and block are moved along in a direction parallelto the axis of the roll and a new portion of the roll is scoured. In the manufacture of sheet metal it is quite common to roll the sheets at such a high temperature that the rolls may be red hot.

Certain difliculties arise in the use of abrasive blocks in the manner described. They are for example subject to breakage so that they have to be changed frequently in general, causing loss of time as wellas the replacement of expensive abrasive blocks. 'This breakage is due partly to the severe mechanical strains produced by the high pressures which are applied to the blocks in conjunction with the high temperatures at-which'they are used, the high temperatures being produced by conduction from the hot rolls and by the friction experienced in scouring the rolls.

I use the following means to reduce the difiiculties referred to above. My abrasive block is illustrated in the accompanying drawingin which 2.

Figure lgives a perspective 'View of one of my fluted roll blocks;-and i; V A

Figure 2 rep resentsdiagrammatically the mplde of application of one ofmy blocks to a rofmm Referring to the drawing in detail, 2 represents a-roll block and 3 represents a diagonal slot :whose plane makes-an acute'angle with thelong edge 4 of the base of the block.

The blocks are-made of a mixture of abrasive grains (of silicon-carbide for ex- PA eNmF me ample) and ceramic .bonding material. This a mixture. is molded to a form similar to that shown in Fig. 1.. The diagonal slots are made in the fresh moldedmaterial with a saw blade ordisk wheel. The width 5 of the gap made is thus smallas compared with its depth below the abrasive surface 60f the block. The

depth of theslots should not be greater than about half. the depth of the block. A certain amount of clearance is thus provided which clearance tends to prevent clogging of the abrasive surface with dbris from the roll.

The slots however also relieve the strains due,

and the cooler portions of the block which lie I adjacent to its support on its mounting. As

has been pointed out these temperature differences may be very large owing to conduction from the hot rolls and the large amount of work performed against large frictional forces. On the other hand the projecting portions 7 which lie between the slots are left sufficiently massive to render them very re; sistant to mechanical forces tending to break them off. This resistance of the projections 7 is'increased' by the dia onal direction of the slotswhich leads to t e distribution of severemechanical stress among the projections to a greater extent than would be the case if the slots 3 were perpendicular to the long edge 4 and therefore parallel to the directionof the frictional forces developed in securing the rolls.

The resistance of he projections to stresses produced by differences of expansion and produced by thelarge frictional forces developed depends on the particular bond used to hold the abrasive grains. I may use therefore bonds which I have found to give the best resistance to mechanical stresses at the temperatures experienced in roll scouring.-

While the application of fluted scouring blocks, has been particularly described with reference to roll scouring I do not wish to limit the use of blocks of the design, shown to such use. Such; blocks may be used in other ways- Within the spirit of the following claims.

I claim:

1. A scouring block having a plurality of slots arranged diagonally to the long axis of theblockysaid slots, being narrow as compared with their depth and extending below: the abrasive surface to not: more. thanhalf the depth of the;block. 1

1 2. The," method of, reducing stressesiinfse curing blockssubjectedto. high temperature contacts which consists in providing the. abrasive, surface with slotswhich are narrow as; compared with their depth and whichare arranged diagonally tothe direction; of the frictional forcesduring operation.

' vented.

3. A scouring block composed mainly. of an abrasive material havinga high thermal conductivity and having a series of narrow slits arranged transversely to the greatestxdimension of the abrasive surface and extending intothe abrasive bodya distance greaterthan the width of the slit whereby temperature stresses in the abrasive are substantially pre- In testimony whereof-I afiix my signature.

' FRANK L. 'BUELL. 

